Many problems occur in connection with care of the teeth, cosmetically as well as therapeutically, such as formation of dental plaque, bacterial growth in dental plaque, dental caries, dental calculus (tartar), periodontal disease and demineralization of teeth. Dental plaque is a complex biofilm that accumulates on the hard tissues (teeth) in the oral cavity. Although over 500 bacterial species comprise plaque, colonization follows a regimented pattern with adhesion of initial colonizers to the enamel salivary pellicle followed by secondary colonization through bacterial adhesion. It is well known that a range of streptococci species belong to the early colonizers. It is therefore important to control the adhesion of these bacteria. A variety of adhesins and molecular interactions underlie the adhesive interactions and contribute to plaque development and ultimately to diseases such as caries and periodontal disease.
The enamel of teeth is comprised of hydroxyapatite. In the mouth a natural equilibrium exists between, on the one hand, hydroxyapatite being dissolved from the enamel of the teeth and, on the other, hydroxyapatite being formed on or in the teeth from substances occurring naturally in the saliva. When the equilibrium is such that the hydroxyapatite is dissolved, a cariogenic condition arises which is referred to as demineralization.
It has long been known that incorporation of fluoride ions into enamel protects it from demineralization. Therefore, fluoride is often incorporated in toothpaste. However, fluoride can give rise to fluorose, especially if the patient is swallowing the toothpaste or another dentrifrice or oral hygiene product, which is often the case, for example for small children. It can also be a problem in areas with rather high amounts of fluoride in the drinking water.
The purpose of this patent application is to propose the use of an indigenous milk protein, osteopontin, added to a dental formulation to control or inhibit the growth of bacteria on the tooth surface and thereby prevent or reduce plaque formation and caries.
There are a couple of patents that describe the use of milk protein fractions, i.e. hydrolysates of casein, Ca phosphopeptides/CPP, and glucomacro-peptide/GMP from renneting of milk for repair of damage to the enamel with the hypothesis that they act as a supply of amorphous calcium phosphate to the enamel.                WO 03/059304 proposes an oral care composition containing a fluoride ion source and CPP fraction. This formulation stabilizes the calcium phosphate added to the oral formulation in an amorphous form and at the same time stabilizes the fluoride level in the formulation.        WO 00/07454 describes GMP which, added to a special food formulation based on milk, has an anticariogenic effect on rats.        
In contrast to CPP and GMP peptides, OPN introduces a new dimension in the oral cavity, through its potential to bioactively influence the attachment of oral organisms to the enamel and thus affect the development of caries. Like CPP and GMP, OPN also has an effect on the levels of amorphous calcium phosphate in the saliva available for tooth repair.
OPN thus has several functions in the dental care context.
The great advantage of using OPN in e.g. toothpaste and mouthwash is that it is a natural protein component in bovine milk and thus there is a limited need for clinical testing.